• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 E
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• pp.1611-1613
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• 1998

The new type of prefabricated joint for 161kV XLPE cable have been developed. we, LG Cable & Machinery Ltd., made an huge contract with an foreign country's Power company for the supply of cable and accessories, the training of jointing and termination work to local personnel, technical assistance by joint venture and the supervision of installation and commissioning. By the end of 1997, one of several routes under the contract successfully finished being constructed and specially tested on site. In operation, now this underground transmission line proves well the reliability and efficiency of prefabricated joint and termination applied first time in foreign country.

• 전기학회논문지
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• 제58권12호
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• pp.2342-2348
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• 2009

Even though underground transmission cable is an essential transmission method to supply stable power for downtown and population center, the interaction of electromagnetic force by fault current is very large comparing to overhead transmission line due to restricted installation space such as tunnel, and close consideration is required for it. This paper presents countermeasures to reduce and release the effect of electromagnetic force with rope binding and installation of spacer and describes its efficacy through three phase short-circuit test, which will be utilized as basic materials for improvement and development of cleat, hanger, etc. to reduce and release effect of electromagnetic force in the future.

• 전기학회논문지
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• 제62권7호
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• pp.905-912
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• 2013

Power system fault analysis is commonly based on well-known symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. In case of balanced fault, such as three phase short circuit, transmission line can be represented by positive sequence impedance only. The majority of fault in transmission lines, however, is unbalanced fault, such as line-to-ground faults, so that both positive and zero sequence impedance is required for fault analysis. When unbalanced fault occurs, zero sequence current flows through earth and skywires in overhead transmission systems and through cable sheaths and earth in cable transmission systems. Since zero sequence current distribution between cable sheath and earth is dependent on both sheath bondings and grounding configurations, care must be taken to calculate zero sequence impedance of underground cable transmission lines. In this paper, conventional and EMTP-based sequence impedance calculation methods were described and applied to 345kV cable transmission systems (4 circuit, OF 2000mm2). Calculation results showed that detailed circuit analysis is desirable to avoid possible errors of sequence impedance calculation resulted from various configuration of cable sheath bonding and grounding in underground cable transmission systems.

• 전기학회논문지
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• 제65권12호
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• pp.2113-2118
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• 2016

The precise detection of electric leakage point of underground power cable is very important to reduce cost and time of maintenance and prevent electric shock accident through expedite repair of electric leakage point. This paper proposes a electric leakage point detection system underground power cable using of half-period modulated transmission waveform and earth electric potential measurement. The developed system is composed of transmitter to generate the wanted pulse waveform, receiver to measure and display earth electric potential by the transmitted pulse in electric leakage point and PC Software program to display of GPS coordinate on detection cable line. The performance of the electric leakage point detection system was tested in the constructed underground cable leakage detection test bed. The test results on signal generation voltage precision of signal transmitter, mean detection earth voltage, mean detection leakage current and electric leakage point detection error showed the developed system can be used in electric leakage point detection underground power cable.

• 한국지리정보학회지
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• 제7권2호
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• pp.69-77
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• 2004

현재 국내에서 관리하고 있는 지하시설물들은 몇몇의 문제점을 가지고 있다. 특히, 한국전력공사의 경우 현장에서 구축되는 지리정보 및 속성정보의 신속한 갱신이 되지 않아 보다 정밀하고 안정된 한국전력 선로관리가 어려운 실정이다. 또한, 토목공사 현장에서 관리감독을 수행하고 있는 한국전력 관계자들은 지리정보체계에 대한 지식과 정보는 부족하지만, 현장에 부합되는 지리정보 및 속성정보를 파악하고 있다. 따라서 보다 효율적인 한국전력의 선로관리를 위해서는 이들의 업무분석내용을 충분히 참조해야 하는데 기존의 한국전력 선로관리시스템의 정보는 그러하지 못한 문제점을 가지고 있다. 본 연구에서는 한국전력공사에서 시설물공사를 통하여 구축된 송 배전 지하시설물에 관한 지리정보 및 속성정보를 이용하여 실무자에게 보다 쉽고 안전하게 유지 관리할 수 있도록 사용자 중심의 송 배전 지하시설물관리시스템을 구축하였다.

• 전기학회논문지
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• 제63권9호
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• pp.1180-1185
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• 2014

This paper describes the effects on SUS tube of power optical fiber composite cable on underground transmission lines. The effects on grounding, air gap between SUS tube and metal sheath, contact resistance between outer semi-conducting layer and metal sheath and grounding of SUS tube application or not are variously analysed using EMTP in normal operating condition as well as single line to ground fault. From these results, in this paper, the scheme for protecting the electrically abnormal phenomena will be established on power-optical fiber composite cable of underground transmission lines. This paper can contribute to specification of grounding reference of SUS tube of optical fiber composite power cable system.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1002-1008
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• 2014

This paper describes insulation design and its reliability evaluation of ${\pm}80kV$ HVDC XLPE cable. Recently, the construction of HVDC transmission system, which is combined overhead line with underground cable, has been completed. This system is installed with existing 154 kV AC transmission line on the same tower. In this paper, the lightning transient analysis is firstly reviewed for selection of basic impulse insulation level and nominal insulation thickness. Then the electrical performance tests including load cycle test and superimposed impulse test based on CIGRE TB 496 are performed to evaluate the reliability of newly designed HVDC cable. There is no breakdown for ${\pm}80kV$ HVDC XLPE cable during electrical performance test. Finally, this system is installed in Jeju island based on successful electrical performance test (Type test). After installation tests are also successfully completed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.491-493
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• 2001

This paper describes the effect of lightning current on combination transmission line. In the paper, an lightning current which can generate 2/80[${\mu}s$]. 20[kA] - 40[kA] waveform is modeled in ATPDraw. The lightning current invaded to the overhead power transmission line propagates to the underground power cable. The simulation was performed to analyze the effect of arrester location and overvoltage occurred in power cable.

• 전기학회논문지
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• 제59권11호
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• pp.1949-1955
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• 2010

This paper describes the characteristic and effectiveness of combined GIL transmission line through lightning surge analysis. In addition the XLPE cable is analyzed in the same condition to compare with GIL. Lighting surge analysis is carried out by EMTP/ATP-Draw to obtain overvoltage of GIL and XLPE cable at service-point and load-out area of underground line. Propagation velocity is calculated in combined transmission lines with GIL and XLPE cable. The overvoltage is also analyzed on GIL and XLPE cable with or without arrester operation. The Analysis results show that overvoltage of GIL is occurred higher than XLPE cable at the same condition. Therefore it is evaluated that the application of GIL at the field should be considered cautiously when more detailed transient analysis, another electrical testes and economic evaluations are implemented.

• 전기학회논문지
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• 제64권2호
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• pp.240-246
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• 2015

Length of most underground power cable in home is not so long. Therefore it is operated without transposition due to low unbalanced ratio. However, if cable length is long, line constant of each cable will be different. Different line constant can induce unbalanced voltage and current of sheath. Also it can induce several induced interference. This paper describes the effectiveness of transposition through sheath component analysis on transposition and untransposition of cable conductor. Especially sheath current and induced voltage are analyzed and compared in case of transposition and untransposition. EMTP is used for modeling and analysis.